The annotation has the following, but I feel uncomfortable about it:-----16.Nxc4I am convinced that you like more this position. White improved the position of his knight (on c4), the a1-rook will get an excellent position on a1, and the black king is more exposed.-----I would rather have a rook on c1 in this position. Doesn't the above mean "the a1-rook will get an excellent position on _c1_," ?

I asked this to admin@chessmasterschool by email 1 week ago, but he/she does not respond to this question.